摘要
据统计,天津沿海地区50年一遇的风暴潮极端增水水位为+4.092m,开展控沉工作后的地面下沉速率约为15mm/a,目前沿岸海挡顶面高程一般为+4.332m。参考孟加拉湾、伦敦、汉堡等沿海地区在2050年海平面上升(取较今高约0.2m的推测值)背景下的极端增水趋势预测(增加0.5m),推测天津沿海地区2050年的极端高水位将增加到+4.792m(4.092m+0.2m+0.5m),现有海挡顶面高程将下沉至+3.687m(以2007年为起算年份)。2050年极端高水位将比届时的海挡顶面高1.105m,由此将加重风暴潮水漫溢致灾的危险。如果再考虑波浪叠加、河口效应、极端海面上升等不确定因素的影响,危险将更加严重。
According to the available statistic data, the 1-in-50-year extreme water level （ewl） caused by storm tides was ＋4.092 m in the coastal area of Tianjin. The land subsidence rate is -15 mm/a after the land subsidence is controlled. Now the elevation of the top of the coastal levee is ＋4.332 m above sea level in general. Following the 0.2m increasing of the projected sea-level-rise, adding extra 0.5m in Bengal Bay, London and Hamburger etc. in 2050 for the extreme high water, we forecast the local ewl will be increased to ＋4.792m （4.092m＋0.2m＋0.5m） in the area in 2050, while the top of levee will be sunk to ＋3.687m at that time （with the starting year of 2007）. As a result, the predicted ewl will be 1.105 m higher than the sunk tops of levees in 2050. This will increase the risk of the flooding of storm tide water and occurrence of a disaster. This risk will be even graver in consideration of the influences of a number of uncertain factors such as wave superposition, estuarine effect and extreme sea level rise.
出处
《地质通报》
CAS
CSCD
北大核心
2008年第6期829-836,共8页
Geological Bulletin of China
基金
中国地质调查局国土资源调查项目《环渤海地区重点地段环境地质调查及脆弱性评价》(编号:1212010540501)
国家“908”专项《我国近海海洋综合调查与评价》资助
关键词
天津
极端高水位
海挡下沉
趋势预测
Tianjin
extreme high water level
coastal levee subsidence
trend prediction
